镍基催化体系硫代硫酸盐高效浸金基础研究

项目名称： 镍基催化体系硫代硫酸盐高效浸金基础研究

项目编号： No.51504293

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 矿业工程

项目作者： 徐斌

作者单位： 中南大学

项目金额： 21万元

中文摘要： 硫代硫酸盐法被广泛认为是最有前途的非氰化浸金方法，但需引入铜、氨以催化浸出，这也导致硫代硫酸盐消耗过高。申请人在前期研究中发现，镍氨、镍柠檬酸、镍焦磷酸替代铜氨催化均可明显降低硫代硫酸盐消耗，且它们的浸金率与铜氨催化基本相当。因此，本项目提出采用镍基催化体系取代传统的铜氨体系以实现硫代硫酸盐高效浸金的思路。拟首先研究配体（L）种类对镍基体系催化硫代硫酸盐浸金的影响及其机理和Ni(Ⅱ)-L配离子与其催化浸金的构效关系，得到优选的镍基催化体系。然后研究该体系催化浸金的电化学机理和金浸出、硫代硫酸盐分解的反应历程及浸出液混合电位对这两种反应的影响。最后研究该优选体系下伴生矿物对硫代硫酸盐浸金的影响及其机理与添加剂对消除有害伴生矿物影响的作用。镍基催化体系取代传统的铜氨体系可避免铜氨配离子对硫代硫酸根的氧化，该项目将为解决硫代硫酸盐耗量大问题提供理论基础，推动硫代硫酸盐法浸金的工业应用。

中文关键词： 硫代硫酸盐；浸金；镍；催化体系；组效关系

英文摘要： Among non-cyanide leaching of gold, thiosulfate leaching is widely recognized as the most promising, in which copper and ammonia are used conventionally for the catalysis of gold leaching. However, this catalytic system also causes the problems that thiosulfate consumption is too high. A preliminary study done by proposer indicated that thiosulfate consumption could be obviously reduced without the decrease of gold leaching percentage when the catalytic system of copper and ammonia was replaced by the system of nickel and ammonia, the system of nickel and citric acid or the system of nickel and pyrophosphoric acid. So, this project proposes the idea that the conventional catalytic system of copper and ammonia is substituted by a nickel base catalytic system for the purpose of high efficient extraction of gold by thiosulfate. At first, the effects of types of ligands(L) on the catalysis of thiosulfate leaching of gold by the nickel base system and their effect mechanisms together with structure-activity relationship between Ni(Ⅱ)-L complex ions and the catalysis of gold leaching will be studied, and an optimized catalytic system is obtained. Afterwards, the electrochemical mechanism of the catalysis of thiosulfate leaching of gold by this optimized system, the reaction mechanisms of gold leaching and thiosulfate decomposition together with the effect of lixivium mixed potential on these two reactions will be studied. In the end, the effects of associated minerals on gold leaching by thiosulfate and their effect mechanisms together with the impacts of additives on the removal of influences of detrimental associated minerals will be studied. The oxidation of thiosulfate by Cu(Ⅱ)-NH3 complex ions can be avoided through the substitution of the nickel base catalytic system in the place of conventional copper and ammonia system. This project will provide a theoretical foundation to solve the problem of high thiosulfate consumption, and thus the industrial application of thiosulfate leaching of gold will be promoted strongly.

英文关键词： thiosulfate;leaching of gold;nickel;catalytic system;constituent-activity relationship